• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.1062-1067
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• 2014

In the present study, a new analytical method was devised for the simultaneous determination of soluble carbohydrates in soybean seeds using high performance liquid chromatography/evaporative light scattering detection (HPLC/ELSD). The limit of quantification (LOQ) for soybean soluble carbohydrates ranged from 5.6~7.6 mg/kg using the HPLC/ELSD method and from 16.2~33.9 mg/kg using the high performance liquid chromatography/refractive index detection (HPLC/RID) method. Therefore, the HPLC/ELSD method was more sensitive than HPLC/RID. The precision values for retention time and peak area of the HPLC/ELSD method were evaluated by inter-day (n=5) and intra-day (n=10) assays using a standard solution. All precision values (CV<2.5%) for soybean soluble carbohydrates were acceptable and fulfilled international acceptance criteria. All linear calibration curves were obtained with a correlation coefficient of $R^2$ >0.999. The contents of soluble carbohydrates for the "Shingikong" (yellow soybean) and "Cheongjakong 3" (black soybean) samples were analyzed using the HPLC/RID and HPLC/ELSD methods. The difference in carbohydrate contents between the two detection methods was significant. Carbohydrate contents in the HPLC/ELSD method were higher than those in the HPLC/RID method. Overall, the HPLC/ELSD method showed satisfactory resolution with a favorable LOQ and reproducibility. Therefore, these results indicate that the HPLC/ELSD method may be applied to determine the contents of soluble carbohydrates in soybean seeds and related food stuffs.

• Journal of The Korean Association For Science Education
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• v.20 no.4
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• pp.542-561
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• 2000

The purpose of this study was to investigate the relationships among elementary school teachers' high school and college backgrounds in science, their attitudes toward teaching science, their science teaching efficacy beliefs, and their instructional strategies. Both quantitative and qualitative research methodologies, were utilized in this study. This paper, however, presents only the results of the quantitative data analysis while expecting to report the qualitative data analysis outcomes afterwards. Four instruments were used to ascertain information concerning teachers' backgrounds in science(the number of high school science courses they took and the grades of courses, the number of college science courses and grades, the number of college science methods courses and grades), attitudes toward teaching science, science teaching self-efficacy beliefs(personal science teaching efficacy and science teaching outcome expectancy), and their instructional strategies(indirect, direct, and mixed methods). A sample of 340 practicing elementary school teachers participated in this study. To determine statistically significant results, Pearson's correlation coefficient was used to relate teachers' backgrounds in science, attitudes toward teaching science, science teaching self-efficacy beliefs and their instructional strategies. The correlation coefficients were statistically significant regarding four variables, teachers' backgrounds in science, attitudes toward teaching science, science teaching self-efficacy beliefs, and instructional strategies investigated in this study. These results can be interpreted that programs of teacher preparations and trainings which include science and science methods courses should help prospective and practicing teachers change in their attitudes and beliefs toward science teaching. It is expected that future studies concerning teachers' attitudes, beliefs, and behaviors toward teaching science can help to improve science teacher education in Korea.

• Journal of Radiation Protection and Research
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• v.33 no.1
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• pp.13-20
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• 2008

The flow rate measurements in a multi-phase flow pipeline were evaluated quantitatively by means of a clamp-on sealed radioisotope based on a cross correlation signal processing technique. The flow rates were calculated by a determination of the transit time between two sealed gamma sources by using a cross correlation function following FFT filtering, then corrected with vapor fraction in the pipeline which was measured by the ${\gamma}$-ray attenuation method. The pipeline model was manufactured by acrylic resin(ID. 8 cm, L=3.5 m, t=10 mm), and the multi-phase flow patterns were realized by an injection of compressed $N_2$ gas. Two sealed gamma sources of $^{137}Cs$ (E=0.662 MeV, ${\Gamma}$ $factor=0.326\;R{\cdot}h^{-1}{\cdot}m^2{\cdot}Ci^{-1}$) of 20 mCi and 17 mCi, and radiation detectors of $2"{\times}2"$ NaI(Tl) scintillation counter (Eberline, SP-3) were used for this study. Under the given conditions(the distance between two sources: 4D(D; inner diameter), N/S ratio: $0.12{\sim}0.15$, sampling time ${\Delta}t$: 4msec), the measured flow rates showed the maximum. relative error of 1.7 % when compared to the real ones through the vapor content corrections($6.1\;%{\sim}9.2\;%$). From a subsequent experiment, it was proven that the closer the distance between the two sealed sources is, the more precise the measured flow rates are. Provided additional studies related to the selection of radioisotopes their activity, and an optimization of the experimental geometry are carried out, it is anticipated that a radioisotope application for flow rate measurements can be used as an important tool for monitoring multi-phase facilities belonging to petrochemical and refinery industries and contributes economically in the light of maintenance and control of them.

• Journal of The Korean Association For Science Education
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• v.33 no.7
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• pp.1367-1384
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• 2013

The purpose of this study was to develop a Science Academic Emotion Scale for Elementary Students. To make a scale, authors extract a core of 14 emotions related to science learning situations from Kim & Kim (2013) and literature review. Items on the scale consisted of 14 emotions and science learning situations. The first preliminary scale had 174 items on it. The number of 174 items was reduced and elaborated on by three science educators. Authors verified the scale using exploratory factor analysis, confirmatory factor analysis, inter-item consistency and concurrent validity. The second preliminary scale consisted of 141 items. The preliminary scale was reduced to seven factors and 56 items by applying exploratory factor analysis twice. The seven factors include: enjoyment contentment interest, boredom, shame, discontent, anger, anxiety, and laziness. The 56 items were elaborated on by five science educators. The scale with 56 items was fixed with seven factors and 35 items to get the final scale by applying confirmatory factor analysis twice. Except for Chi-square and GFI (Goodness of Fit Index), other various goodness of fit characteristics of the seven factors and 35 items model showed good estimated figures. The Cronbach of the scale was 0.85. The Cronbach of seven factors are 0.95 in enjoyment contentment interest, 0.81 in boredom, 0.87 in shame, 0.82 in discontent, 0.87 in anger, 0.77 in anxiety, 0.81 in laziness. The correlation coefficient was 0.59 in enjoyment contentment interest, 0.54 in anxiety, 0.42 in shame, and 0.28 in boredom, which were estimated using the Science Academic Emotion Scale and National Assessment System of Science-Related Affective Domain (Kim et al., 1998). Based on the results, authors judged that the Science Academic Emotion Scale for Elementary Students achieved an acceptable validity and reliability.

• Korean Journal of Veterinary Service
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• v.37 no.2
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• pp.111-122
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• 2014

The present study was designed to explore the antioxidant effect of Bamboo powder and its immunoreactivity in pigs. We investigated the functional properties of Bamboo extracts by means of measuring the contents of total polyphenols and flavonoid as well as determining ABST, DPPH radical scavenging activity, and hydroxyl radical scavenging activity and anticancer activity. The total phenolic compound and flavonoids contents of Bamboo extracts were 171.25 mg/g and 127.5 mg/g, respectively. The DPPH radical, hydroxyl radical, ABST radical scavenging activity of Bamboo extracts were 17.3%, 12.5% and 21.5%, respectively. Evidenced by MTT and cell cycle assay, Bamboo dose-dependently inhibited the cell proliferation and induced G0/G1-phase arrest in CHO cells at concentrations of 100, 250, and 500 ${\mu}g/ml$ Bamboo extracts. More than 80% of apoptotic cells were observed by staining with annexin V in 500 ${\mu}g/ml$ Bamboo-treated CHO cells, indicating that Bamboo had potent anticancer activities. Next, to investigate the effect of Bamboo on cytokine, immunoglobulin concentration, and blood compositions, flatting pigs were fed with Bamboo powder for 38 days. Flatting pigs were divided into 4 groups; basal diet (control), basal diet supplemented with 1% Bamboo powder (T1), 2% Bamboo powder (T2), and 3% Bamboo powder (T3). The level of hemoglobin increased in the all Bamboo-fed groups compared with the normal control group. In particular, platelet levels in the all Bamboo-treated groups increased by approximately 90% compared with the levels from pig on a normal control. Serum levels of immunoglobulins (IgG, IgA) in the pigs fed Bamboo powder were modestly increased, and the interferon-${\gamma}$ level also was strongly increased in 2% or 3% Bamboo-fed groups compared with the levels in control groups. Together, these results demonstrated that Bamboo extracts had an effective capacity of scavenging for ABTS, DPPH, and hydroxyl radicals and showed correlation with potent phenol and flavonoid contents, thus suggesting its antioxidant potential. Moreover, administration of Bamboo in 2~3% improved blood parameters and platelets, and especially immunity-related ones such as IgG, IgA, and interferon-${\gamma}$, leading to be potential feed additives in flatting pigs.

• Journal of Life Science
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• v.25 no.6
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• pp.680-685
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• 2015

Previously, cellulase and xylanase producing microorganism, Bacillus subtilis NC1, was isolated from soil. Based on the 16S rRNA gene sequence and API 50 CHL test the strain was identified as Bacillus subtilis, and named as B. subtilis NC1. We cloned and sequenced the genes for cellulase and xylanase. Plus, the deduced amino acid sequences from the genes of cellulase and xylanase were determined and were also identified as glycosyl hydrolases family (GH) 5 and 30, respectively. In this study to optimize the medium parameters for cellulase production by B. subtilis NC1 the RSM (response surface methodology) based on CCD (central composite design) model was performed. Three factors, tryptone, yeast extract, and NaCl, for N or C source were investigated. The cellulase activity was measured with a carboxylmethyl cellulose (CMC) plate and the 3,5-dinitrosalicylic acid (DNS) methods. The coefficient of determination (R²) for the model was 0.960, and the probability value (p=0.0001) of the regression model was highly significant. Based on the RSM, the optimum conditions for cellulase production by B. subtilis NC1 were predicted to be tryptone of 2.5%, yeast extract of 0.5%, and NaCl of 1.0%. Through the model verification, cellulase activity of Bacillus subtilis NC1 increased from 0.5 to 0.62 U/ml (24%) compared to the original medium.

• Korean journal of food and cookery science
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• v.16 no.5
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• pp.437-444
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• 2000

The purpose of this study were to identify customer expectation, perception and satisfaction of foodservice quality to analyze the influencing factors on foodservice quality and finally to provide basic information for the improvement of foodservice quality. Among expectation scores of food quality attributes, ‘hygiene of food(3.27)’received the highest score. In expectation scores of service quality attributes,‘hygiene of tableware(3.40)’was the most important. Satisfaction of ‘appropriate 1 portion size(-0.11)’was the highest scored, while‘dealing with complaints on meals(-0.70)’was the most dissatisfied one. Satisfaction was highly correlated with‘providing preferred menu(r = -0.62)’of food quality expectation. It was highly correlated with‘dealing with complaints on meals(r = -0.61)’of service quality expectation. Expectation and perception of foodservice as 2.25 and 2.90 out of 5, respectively, which suggests that foodservice needs to be improved. The attributes identified in Quadrant A, which was labelled‘focus here’and supposed to indicate the areas of high expectation but in low perception, was hygiene of carts holding used trays. The results of expectation and perception analysis indicated the areas that the attention of management should be given to improve quality of foodservice. The stepwize regression analysis suggested that foodservice expectation and perception explaints around 56.7% of the variation in general customer satisfaction.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.7
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• pp.667-678
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• 2002

In this paper, a new radiating structure with a multi-layered two-dimensional metallic disk array was proposed for shaping the flat-topped element pattern. It is an infinite periodic planar array structure with metallic disks finitely stacked above the radiating circular waveguide apertures. The theoretical analysis was in detail performed using rigid full-wave analysis, and was based on modal representations for the fields in the partial regions of the array structure and for the currents on the metallic disks. The final system of linear algebraic equations was derived using the orthogonal property of vector wave functions, mode-matching method, boundary conditions and Galerkin's method, and also their unknown modal coefficients needed for calculation of the array characteristics were determined by Gauss elimination method. The application of the algorithm was demonstrated in an array design for shaping the flat-topped element patterns of $\pm$20$^{\circ}$ beam width in Ka-band. The optimal design parameters normalized by a wavelength for general applications are presented, which are obtained through optimization process on the basis of simulation and design experience. A Ka-band experimental breadboard with symmetric nineteen elements was fabricated to compare simulation results with experimental results. The metallic disks array structure stacked above the radiating circular waveguide apertures was realized using ion-beam deposition method on thin polymer films. It was shown that the calculated and measured element patterns of the breadboard were in very close agreement within the beam scanning range. The result analysis for side lobe and grating lobe was done, and also a blindness phenomenon was discussed, which may cause by multi-layered metallic disk structure at the broadside. Input VSWR of the breadboard was less than 1.14, and its gains measured at 29.0 GHz. 29.5 GHz and 30 GHz were 10.2 dB, 10.0 dB and 10.7 dB, respectively. The experimental and simulation results showed that the proposed multi-layered metallic disk array structure could shape the efficient flat-topped element pattern.

• Journal of Radiation Protection and Research
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• v.27 no.3
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• pp.147-154
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• 2002

Purpose : Measurement of transmission dose is useful for in vivo dosimetry of QA purpose. The objective of this study is to develope an algorithm for estimation of tumor dose using measured transmission dose for open radiation field. Materials and Methods : Transmission dose was measured with various field size (FS), phantom thickness (Tp), and phantom chamber distance (PCD) with a acrylic phantom for 6 MV and 10 MV X-ray. Source to chamber distance (SCD) was set to 150 cm. Measurement was conducted with a 0.6 co Farmer type ion chamber. Using measured data and regression analysis, an algorithm was developed lot estimation of expected reading of transmission dose. Accuracy of the algorithm was tested with flat solid phantom with various settings. Results : The algorithm consisted of quadratic function of log(A/P) (where A/P is area-perimeter ratio) and tertiary function of PCD. The algorithm could estimate dose with very high accuracy for open square field, with errors within ${\pm}0.5%$. For elongated radiation field, the errors were limited to ${\pm}1.0%$. Conclusion : The developed algorithm can accurately estimate the transmission dose in open radiation fields with various treatment settings.

• Tuberculosis and Respiratory Diseases
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• v.48 no.1
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• pp.54-66
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• 2000

Background: Pneumoconiosis, like other chronic respiratory diseases, is essentially incurable and, for many, progressive. While improved survival time is an important aim of treatment, there is growing recognition that for some people, improving the quality of life is more important than extending the length of life. Currently the measurement of the quality of life is used to assess the efficacy of therapeutic agents. Methods: Sixty-three pnemoconiotics who were admitted to St. Mary's Hospital between April and August 1999 were interviewed using COOP charts, Chronic Respiratory Questionnaire(CRQ) and Pneumoconiotic Respiratory Questionnaire(PRQ), a newly developed questionnaire concerning clinical and socioeconomic features of pneumoconiotics. Also, ILO classification of the chest film, pulmonary function test, and arterial blood gas analysis of the patients were evaluated. The scores between Industrial Accident Compensation Insurance(IACI) covered and uncovered patients and between clinically stable and unstable patients were compared. Results: Domains of CRQ and PRQ showed a high internal consistency reliability($\alpha$=0.86-0.89, 0.77-0.81) except the dyspnea domain($\alpha$=0.63) of CRQ. The scores on the CRQ and PRQ showed statistically significant correlations with the results of COOP charts, pulmonary function test and arterial blood gas analysis. The dyspnea domain and social activity domain of the PRQ showed significant difference between IACI covered and uncovered patients and between clinically stable and unstable patients. Conclusion : Korean translation of the Chronic Respiratory Questionnaire and the newly developed Pneumoconiotic Respiratory Questionnaire are reliable and valid methods and are likely to be useful in measuring the quality of life in patients with the chronic respiratory disease including pneumoconiosis.